<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script type="text/javascript" src="../script/jquery-1.7.2.js"></script>
    <script type="text/javascript">
        $(function(){
            $('#testDiv').css("color","red");

            var $btns = $("button");
            for (var i = 0; i < $btns.length; i++){
            	alert($btns[i]);
            }
        });
    </script>
</head>
<body>
    <div id="testDiv">at gui gu is very good12</div>
    <button id="dom2dom">dom 调用 dom</button>
    <button id="dom2jq">dom 调用 jq</button>
    <button id="jq2jq">jq 调用 jq</button>
    <button id="jq2dom">jq 调用 dom</button>
</body>
</html>